The present invention relates generally to a system and method for visually conveying information and more particularly to a system and method for conveying information by modifying the visual attributes of visual objects to reflect the value of one or more variables.
Individuals often have the need to visually convey information to others. In the past, standard tables and charts have been used to express such information. A standard table consists of a systematic arrangement of rows and columns of interrelated data. An example of such a table is shown below in Table 1.
A standard chart consists of a graphical representation of the relationships between two or more interrelated variables. An example of such a chart, depicting the corresponding X and Y coordinates of a moving projectile, is shown in FIG. 1.
Generally, all of the entries in a standard table are presented in the same format. For example, all entries in the table of FIG. 1 have the same font (Times), the same font size (12 point), and the same font color (black). Thus, it is difficult to emphasize certain entries within standard tables.
Similarly, all of the markers in a standard chart are also normally presented in the same format. For example, all of the markers in the chart of FIG. 1 have the same line width (0.75 point), the same marker size (xe2x85x9 inch), and the same marker shape (circular). Thus, it is also difficult to emphasize entries within standard charts.
It is often desirable to visually demonstrate the relationships between more than two interdependent variables in a table. For example, in the projectile example discussed above, the user may wish to present information regarding the movement of the projectile along a Z-axis perpendicular to both the X-axis and the Y-axis (i.e., use a two-dimensional table for a three-dimensional representation). In addition, the user may wish visually represent information concerning the time, after the object is set into motion, at which the projectile reaches each point along the X-axis.
Traditionally, the relationships between four interdependent variables have been depicted in a tabular format by creating a table having four columns; one column for each independent variable. Thus, in the example discussed above, an author could use known methods to create a table depicting the relationships between the four interdependent variables (X-position, Y-position, Z-position, and time) by adding two new columns to the table shown in FIG. 1. Such a table is shown below as Table 2. The disadvantage of this technique is that it makes the table larger and more complex than a table having fewer columns.
It is also often desirable to visually demonstrate the relationships between more than two interdependent variables in a two-dimensional chart. Traditionally, authors have depicted the relationships between three interdependent variables in a chart by first creating a two-dimensional chart to display the relationship between two of the interdependent variables, as shown in FIG. 2, and then coloring the chart""s markers to represent the relationship between the third interdependent variable and the two variables already depicted. Such a technique is commonly used in topographical maps to indicate changes in elevation.
Thus, returning to the example above, an author could use known techniques to indicate the Z-position of the projectile in the chart of FIG. 2 by first establishing a legend of colors corresponding to various Z-coordinates and then coloring each of the markers according to the legend. An example of such a technique is shown in FIG. 2 below.
Authors have not been successful in developing an elegant technique for displaying the relationships between four or more interdependent variables in a two-dimensional chart. Authors often indicate values of a fourth variable by writing the value of the fourth variable next to the appropriate marker as shown below in FIG. 3. However, such a technique causes charts to be cluttered and difficult to read.
Thus, there is a need for a method for emphasizing certain entries in visual representations of information such as tables and charts. There is also a need for a method for increasing the amount of information that can be displayed within a table without increasing the physical size of the table. Similarly, there is a need for a method of increasing the amount of information that can be displayed within a chart without making the chart difficult to read. Thus, there is a need for a method of increasing the information density within a table or a chart. There is also a need for a method of efficiently representing the interrelationships between four or more interrelated variables in a two-dimensional chart.
The present invention solves the problems associated with standard visual data presentation techniques by using visual attributes (such as color, fill type, border width, line width, line style, font size, marker size and marker type) of characters or markers to convey information to the reader. In particular, the invention emphasizes data within a table or a chart by modifying the visual attributes of characters or markers within the table or chart if the characters or markers represent values meeting specified criteria. For example, the invention can emphasize all data points with negative values by increasing the line width of the characters or markers that represent data points having values less than zero.
Similarly, the invention can increase information density within a table or chart and thus, for example, elegantly represent the relationships between four or more interrelated variables in a two-dimensional chart. The invention accomplishes this by associating data values with corresponding visual attributes. These visual attributes are then applied to a character or marker within a table, chart, or other visual representation to visually express the data values. Thus, for example, the invention might use the size of a marker within a chart to indicate speed. In such a chart, large markers might indicate greater speed and smaller markers might indicate lessor speed within a pre-determined range.
The present invention performs the above-described techniques by means of a formatting object that is executed on a computer system. The formatting object accomplishes this by defining at least one format map that comprises one or more mapping segments. Each mapping segment includes a beginning boundary value, an ending boundary value, at least one beginning visual attribute corresponding to the beginning boundary value, and at least one ending visual attribute corresponding to the ending boundary value. During execution, the format map is associated with a particular variable for which at least one data value is retrieved from a data file. For each mapping segment, the system associates the beginning boundary value of the mapping segment with the beginning visual attribute of the mapping segment to define a first mapping point, and associates the ending boundary value of the mapping segment with the ending visual attribute of the mapping segment to define a second mapping point. If a given data value falls between the beginning and ending boundary values of a given mapping segment, the system applies interpolation techniques in combination with the data corresponding to the first and second mapping points to determine one or more visual attributes corresponding to the data value. The system may then express the data value by associating these visual attributes with a visual object, such as a character in a table or a marker in a chart.
The present invention can express the boundary values of each mapping segment as real numbers (absolute boundary values) or as percentages (relative boundary values). Absolute boundary values do not change when a given set of data is received by the formatting object. Thus, if the formatting object receives a data value that is outside of the absolute boundary values of all of the mapping segments within a given format map, the system will not apply the format map to that data value.
Relative boundary values are expressed in relation to the ranges of data values received by the formatting object. These relative boundary values are converted into absolute boundary values for each set of data received by the system. Thus, relative boundary values can change in response to each set of data received by the system. For example, if a mapping segment is defined to have a beginning boundary value of 20% and an ending boundary value of 100%, and the formatting object receives data values for a given variable that range between 0 and 100, the mapping segment will have beginning and ending boundary values of 20 and 100, respectively, for that particular set of data. If the system later receives a set of data for the same variable that ranges between 0 and 200, the mapping segment will have beginning and ending boundary values of 40 and 200, respectively.
If desired, a given mapping segment may be defined to have mixed types of boundary values. For example, a given mapping segment may be defined to have a relative beginning boundary value and an absolute ending boundary value.
In another aspect of the invention, the various mapping segments within a format map are defined to have two or more equal divisions. If a mapping segment is defined to have such divisions, the formatting object divides the mapping segment equally into the number of divisions specified by the author or user. During this process, the formatting object defines each division to have a beginning division value and an ending division value. The system then associates a visual attribute with each division. During execution, the formatting object receives a given range of data values for a given variable, and then converts any relative boundary values into absolute boundary values, and any relative division values into absolute division values. Next, for each data value, the system determines whether the data value falls between beginning and ending division values of a particular division within a mapping segment of the format map. If so, the system associates the data value with the visual attribute corresponding to that division. The system may then express the data value by associating the identified visual attribute with an appropriate visual object.
In yet another aspect of the invention, a given format map includes a plurality of mapping segments. These mapping segments can overlap, and, as discussed above, can include different types of boundary values. The format map can comprise a first mapping segment that has absolute beginning and ending boundary values, and a second mapping segment that has relative beginning and ending boundary values. Similarly, a given chart or table can include a plurality of format maps.
The various aspects of the present invention may be more clearly understood and appreciated from a review of the following detailed description of the disclosed embodiments and by reference to the appended drawings.